A conventional packing machine for applying a heat-shrinkable capsule and/or a heat-shrinkable plasti-shield and/or a heat-shrinkable plastic wrap onto a package generally has a cutting device for cutting a roll of foil into sheets. The foil is extended via a series of rollers and a gripping mechanism onto a die wherein the foil is adjacent to a supportive surface thereof. Then, the cutting device is operated to cut the foil to obtain a sheet with a predetermined length. Thereafter, the cut heat-shrinkable plastic sheet is transferred and, for example, wrapped around a package (for example, a folded paper box for a bar of soap) by means of an arrangement of specifically designed jigs. Finally, the soap box, which has been loaded with a bar of soap therein, is subjected to heat to shrink the plastic sheet so that it may be very be tightly fastened onto the box to form a protective film for the paper soap box.
Conventionally, the cutting device for the above-mentioned packing machine has a linear movement for its cutting tool. This means that when the heat shrinkable plastic foil is extended onto the die and located adjacent to the supportive surface, which can be monitored by electrical-optical sensors, the cutting tool of the cutting device is linearly extended to cut the foil to obtain a sheet, and, then, linearly retracted to its original position to await the next cutting operation.
Such a conventional cutting device has a low cutting efficiency, which causes the subsequent operating steps of the packing machine to be deferred to a certain extent; thus, the operating efficiency of the packing machine can not be promoted.
The present invention is disclosed to afford an improved foil cutting device which can mitigate and/or obviate the above-mentioned problem concerning the conventional foil cutting device.